// @(#)QueueNI.java   4/2003
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package drcl.inet.core;

import drcl.data.*;
import drcl.comp.Port;
import drcl.net.*;
import drcl.util.queue.FIFOQueue;

/**
 * Base class for implementing a combo component that combines the functioins
 * of both a buffer and a network interface card.
 */
public abstract class QueueNI extends NI_LinkEmulation
{
  protected boolean byteMode = true;
  Port dequeuePort = addPort(".deq", false);

  public QueueNI()
  {  super();  }
  
  public QueueNI(String id_)
  {  super(id_);  }
  
  public void duplicate(Object source_) 
  {
    super.duplicate(source_);
    QueueNI that_ = (QueueNI)source_;
    byteMode = that_.byteMode;
  }

  protected void transmit(Packet p)
  {
    if (dequeuePort.anyPeer())
      dequeuePort.doSending(p);
    double readyTime_ = getTime() + (double)(p.size << 3)/ bw;
    forkAt(pullPort, this, readyTime_);
    if (linkEmulation)
      sendAt(downPort, p, readyTime_ + propDelay);
    else
      sendAt(downPort, p, readyTime_);
  }
  
  public String info()
  {
    return super.info()
      + drcl.util.StringUtil.finalPortionClassName(getClass()) + ", in "
      + getMode() + " mode" + "\n"
      + "Occupied/Capacity = " + getSize() + "/" + getCapacity() + "\n";
  }

  /**
   * Sets the operation mode. Byte mode is the default and only acceptable mode.
   * @param mode_ either "packet" or "byte".
   */
  public void setMode(String mode_)
  {
    byteMode = mode_.equals(drcl.inet.InetConstants.BYTE_MODE);
  }
  
  public String getMode()
  {
    return byteMode? drcl.inet.InetConstants.BYTE_MODE:
      drcl.inet.InetConstants.PACKET_MODE;
  }

  /** Sets the capacity of the queue. */
  public abstract void setCapacity(int capacity_);
  
  /** Returns the capacity of the queue. */
  public abstract int getCapacity();
  
  /** Returns the current size of the queue. */
  public abstract int getSize();
}
